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MEDLINE Indexing Online Training Course

Category N - Health Care

Indexing Principles

Category N contains the MeSH terms for the field of health care. The terms are divided into six broad subcategories.

  • Category N1 contains the MeSH terms for population characteristics demographic terms, health status terms for different population groups, and socioeconomic terms.
  • Category N2 - contains the MeSH terms for health care facilities, manpower and services.
  • Category N3 contains the MeSH terms for the economic and organizational aspects of health care - economics, insurance, planning, organizations and agencies, social control, legislation and policy terms.
  • Category N4 contains the MeSH terms for health services administration organizational aspects of health care, patient care management, and quality of health care.
  • Category N5 contains the MeSH terms important for health services researchers. All terms in this category can also be found in other MeSH categories. This Category includes terms for health care delivery, ethics, health services research, quality assurance of health care, and quality of health care.
  • Category N6 contains the MeSH terms important for the environment and public health.

Category N terms tend to be indexed as IM concepts, although, some are annotated to be indexed as NIM concepts. Always check the MeSH record.

When the Category N term is indexed as an IM concept, it is usually coordinated with a Category Z geographical term country, province, state, city.

Do not routinely add Category N terms to clinical articles. Most clinical studies take place in a health facility, and adding a Category N term to a purely clinical article is misleading. For example, an article describing a diagnostic procedure in a hospitalized patient, does not require the MeSH term HOSPITALIZATION. On the other hand, an article describing administrative aspects of patient hospitalization (regardless of the patient disease), will be appropriately indexed with HOSPITALIZATION as IM concept.

Articles indexed with Category N2-4 terms as IM concepts should be forwarded for review to the Health Administration specialist.

Of special importance are several MeSH headings for Epidemiologic methods, for example:

  • Case-Control Studies
  • Cohort Studies
  • Follow-Up Studies
  • Longitudinal Studies

These concepts are very important for researches in the field of epidemiology. They are indexed (usually as an NIM concept) routinely, if the article mentions them. These terms are also located in the Category E5 and N5 trees.

Last Reviewed: March 10, 2015